AIRWORTHINESS DIRECTIVE
For the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.1 (1) of CASR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.
Airbus Industrie A319, A320 and A321 Series Aeroplanes
AD/A320/152 Auxiliary Power Unit Alternating Current
Generator
4/2004
Applicability: A319, A320 and A321 series aeroplanes, all serial numbers, equipped with Hamilton Sundstrand Auxiliary Power Unit (APU) alternating current (AC) generator part number (P/N) 5906732, 5909006 or 5910047 with modification up to 17 incorporated.
Note 1: Documentation from both Airbus and the French Direction Générale de l’Aviation Civile refer to the AC generators having amendments up to 17 rather than modifications.
Note 2: No action is required by this Airworthiness Directive for aircraft that have embodied Airbus Modification 32614 during production or incorporated Airbus Industrie Service Bulletin (SB) A320-24-1106 whilst in service, provided that no generator has been replaced since the modification or SB was incorporated.
Requirement: Unless already accomplished, replace all four bolts that retain the electrical receptacle of the APU AC generator with bolts P/N 5910191-30 and lock wire the bolts in accordance with the instruction given in SB A320-24-1106 (Hamilton Sundstrand Goodrich Power Systems SB 90EGS01AG-24-18 is also applicable).
Note 3: DGAC AD F-2004-019 refers.
Compliance: Before 30 October 2005.
This Airworthiness Directive becomes effective on 15 April 2004.
Airbus Industrie A319, A320 and A321 Series Aeroplanes
AD/A320/152 (continued)
Background: The DGAC has advised that an operator reported a blast in the APU compartment, that blew open the APU compartment doors, damaging aircraft’s tail cone structure and the left elevator surface.
Analysis revealed, that vibrations in APU AC generators loosened the electrical receptacle retaining bolts, which lead to oil vapor leakage. This leakage, associated with an electrical arc at the electrical receptacle, was determined to be the cause of the blast.
James Coyne
Delegate of the Civil Aviation Safety Authority 4 March 2004
The above AD is notified in the Commonwealth of Australia Gazette on 24 March 2004.
Overview
The Airworthiness Directive AD/A320/152 was enacted in 2004 by the Civil Aviation Safety Authority (CASA) under the Civil Aviation Act 1988, addressing an unsafe condition identified in Airbus Industrie A319, A320, and A321 series aeroplanes equipped with specific Hamilton Sundstrand Auxiliary Power Unit (APU) alternating current generators. The directive was prompted by an incident where vibrations led to loosened bolts in the APU AC generator, resulting in an oil vapor leak and subsequent blast that damaged the aircraft. The policy objective of the AD is to ensure the continued airworthiness of these aircraft by mandating the replacement of specific bolts retaining the electrical receptacle of the APU AC generator, thereby mitigating the risk of similar incidents. Compliance with this directive was required before 30 October 2005.
Scope and Application
The Airworthiness Directive (AD) issued under subregulation 39.1 (1) of the Civil Aviation Safety Regulations 1998 applies to Airbus Industrie A319, A320 and A321 series aeroplanes, all serial numbers, equipped with specific Hamilton Sundstrand Auxiliary Power Unit (APU) alternating current (AC) generator parts. Specifically, the AD targets generators with part numbers 5906732, 5909006 or 5910047 with modifications up to 17 incorporated. Aircraft that have already embodied Airbus Modification 32614 during production or incorporated Airbus Industrie Service Bulletin (SB) A320-24-1106 whilst in service, without having replaced any generator since, are exempt from this AD. The AD mandates the replacement of all four bolts retaining the electrical receptacle of the APU AC generator with bolts P/N 5910191-30 and locking the bolts in accordance with specified instructions. The directive applies nationally across Australia, and compliance must be achieved before 30 October 2005. The AD became effective on 15 April 2004.
Key Provisions
The Airworthiness Directive AD/A320/152 (section 1) applies to Airbus Industrie A319, A320 and A321 series aeroplanes, all serial numbers, equipped with specific Hamilton Sundstrand Auxiliary Power Unit (APU) alternating current (AC) generator parts. It does not apply to aircraft that have incorporated Airbus Modification 32614 during production or Airbus Industrie Service Bulletin (SB) A320-24-1106 whilst in service, provided no generator has been replaced since the modification or SB was incorporated (section 2). The directive requires the replacement of all four bolts retaining the electrical receptacle of the APU AC generator with bolts P/N 5910191-30 and locking the bolts in accordance with the instructions given in SB A320-24-1106 (section 3). This action is necessary to correct an unsafe condition that could lead to oil vapor leakage and subsequent blast in the APU compartment, causing damage to the aircraft's tail cone structure and the left elevator surface (section 4). Compliance with this directive is mandatory before 30 October 2005 (section 5).
Operators and owners of the affected aircraft must ensure that the specified maintenance action is completed in accordance with the directive's requirements and within the stipulated timeframe. This includes identifying the aircraft that fall under the applicability section, procuring the necessary replacement bolts and following the instructions for their installation and locking, and ensuring that the work is completed and documented properly (section 6). Failure to comply with the directive may result in the aircraft being considered unairworthy, potentially leading to grounding of the aircraft until the required actions are completed (section 7).
The AD carries significant implications for non-compliance. Under the Civil Aviation Safety Regulations 1998, failure to comply with an Airworthiness Directive can result in civil penalties, including fines. In addition, non-compliance may lead to enforcement actions by the Civil Aviation Safety Authority (CASA), potentially resulting in the suspension or revocation of the aircraft's certificate of airworthiness (section 8). The maximum penalties for breaches of these regulations can include substantial fines and, in severe cases, imprisonment (section 9). Operators are therefore strongly advised to adhere to the requirements of this directive to avoid these serious consequences.